G. Whitesides and his team at Harvard University have developed a prototype for an inexpensive, highly practical rapid test that can be used to carry out several biological tests simultaneously on a single drop. As they describe in the journal Angewandte Chemie, their tests are based on tiny pieces of paper onto which defined, millimeter-sized channels are printed.

Share This

Testing biological fluids such as blood and urine is essential for both diagnostics and routine checks. In remote, non-industrialized regions or for emergency on-the-spot diagnosis, current methods of laboratory analysis are far too complicated. George M. Whitesides and his team at Harvard University in Cambridge, Massachusetts (USA) have now developed a prototype for a new class of inexpensive, highly practical rapid tests that can be used to carry out several biological tests simultaneously on a single drop. As they describe in the journal Angewandte Chemie, their tests are based on tiny pieces of paper onto which defined, millimeter-sized channels are printed.

Related Articles

To produce these, highly absorbent paper is treated with a photosensitive coating and covered with a mask that is the negative of the desired pattern. When the paper is irradiated with UV light through the mask, the molecules of the photosensitive coating change so that subsequent heating converts them to a continuous polymer layer. The untreated coating under the mask can be washed away, while the polymer layer on the irradiated spots is bound fast to the paper. This system allows the researchers to produce a tiny system of channels separated from each other by “channel walls” made of the water-repellent polymer.

As a prototype, Whitesides and his team selected a clover-leaf-shaped channel system: A main channel branches into three tiny chambers. Different color reagents are introduced into each of these chambers and are allowed to dry. The first chamber contains a reagent for a glucose test and the second a protein test; the third is a control. When a drop of liquid is introduced, the capillary action of the paper quickly sucks it up and transports it into all three chambers. A series of tests with artificial urine demonstrated that the intensity of the (simultaneously occurring) color reactions corresponds to the glucose and protein concentrations. The sensitivity of detection is comparable to conventional glucose and protein test strips.

Crucial to implementation in the field, the tests are not affected by contamination by dust, dirt, or plant materials, because these particles are not absorbed by the paper.

More From ScienceDaily

More Matter & Energy News

Featured Research

Mar. 3, 2015 — By examining the forces that the segments of mosquito legs generate against a water surface, researchers have unraveled the mechanical logic that allows the mosquitoes to walk on water, which may ... full story

Mar. 3, 2015 — Researchers have developed a new way of rapidly screening yeasts that could help produce more sustainable biofuels. The new technique could also be a boon in the search for new ways of deriving ... full story

Mar. 3, 2015 — Major cities in the UK are falling behind their international counterparts in terms of their use of smart technologies, according to a new study. The research has found that smart cities in the UK, ... full story

Mar. 3, 2015 — Scientists have explored friction at the microscopic level. They discovered that the force generating friction is much stronger than previously thought. The discovery is an important step toward ... full story

Mar. 3, 2015 — Micro-drones are already being put to use in a large number of areas: These small aircraft face extensive requirements when performing aerial observation tasks or when deployed in the field of ... full story

Mar. 3, 2015 — Recent research contributes to the effort to determine the nature of dark matter, one of the most important mysteries in physics. As indirect evidence provided by its gravitational effects, dark ... full story

Mar. 3, 2015 — Physicists have shown for the first time that electrons in graphene can be moved along a predefined path. This movement occurs entirely without loss and could provide a basis for numerous ... full story

Featured Videos

Forensic Holodeck Creates 3D Crime Scenes

Reuters - Innovations Video Online (Mar. 3, 2015) — A holodeck is no longer the preserve of TV sci-fi classic Star Trek, thanks to researchers from the Institute of Forensic Medicine Zurich, who have created what they say is the first system in the world to visualise the 3D data of forensic scans. Jim Drury saw it in operation.
Video provided by Reuters

Solar Plane Passes New Test Ahead of World Tour

AFP (Mar. 2, 2015) — A solar-powered plane made a third successful test flight in the United Arab Emirates on Monday ahead of a planned round-the-world tour to promote alternative energy. Duration: 01:05
Video provided by AFP

Electric Hydrofoiling Watercraft Delivers Eco-Friendly Thrills

Reuters - Innovations Video Online (Mar. 2, 2015) — The Quadrofoil is a high-tech electric personal watercraft that its makers call a &apos;sports car for the water&apos;. When it hits 10 km/h, the Slovenian-engineered Quadrofoil is lifted above the water onto four wing-like hydrofoils where it &apos;flies&apos; above the surface with minimal water resistance. Matthew Stock reports.
Video provided by Reuters

Related Stories

Nov. 19, 2014 — Flexible electronic sensors based on paper -- an inexpensive material -- have the potential to some day cut the price of a wide range of medical tools, from helpful robots to diagnostic tests. ... full story

May 21, 2014 — To the relief of patients diagnosed with hepatitis C, the US Food and Drug Administration approved two new treatments late last year, and a few more are on the way. Now scientists are solving another ... full story

Nov. 18, 2013 — Pioneering research that could transform the care of cancer patients or people with infections in their own homes has received a significant grant to help develop laser-printed paper-based sensors ... full story

Mar. 8, 2012 — Inspired by the paper-folding art of origami, chemists have developed a 3-D paper sensor that may be able to test for diseases such as malaria and HIV for less than 10 cents a pop. The sensors can be ... full story

Nov. 3, 2010 — Scientists are reporting the development of a simple, built-in timer intended to improve the accuracy of paper tests and test strips for diagnosing diseases inexpensively at-home and ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.